Drug trafficking has long been known to fund terrorist groups, and the DEA wanted to put this aircraft to use in Afghanistan.

With help from the Department of Defense, the agency planned to outfit the $8.6 million, twin-propeller passenger aircraft with surveillance equipment and other bells and whistles.

More than seven years and $86 million later, however, the plane still rests on its jacks. An audit (pdf) from the Office of the Inspector General released Wednesday says it never flew in Afghanistan and is unlikely to do so ever, as this July marks one year since the DEA wound down its operations in the country.

The plan to buy and modify the plane, dubbed the Global Discovery program, ended up costing four times as much as the agency's original $22 million estimate, in part because the DEA bought a model that didn't meet its technical needs and failed to keep the records necessary to guarantee a DOD subcontractor performed the right changes to the aircraft, according to the report.

"We believe that the more than $86 million spent on the purchase and modification of the DEA's ATR 500 aircraft with advanced surveillance capabilities to support the DEA's counternarcotics mission in Afghanistan has been an ineffective and wasteful use of government resources," the 68-page report states.

Problems with the Global Discovery Program began even before the DEA and DOD officially launched the operation, according to the report, which grew out of a whistleblower's tip.

The DEA set out in July 2008 to buy an ATR 320 or ATR 500 aircraft, two models of passenger plane that boast large, twin propellers and a rounded body directly beneath a pair of long wings.

Auditors found that the agency expected to spend $5.8 million on the plane and received six offers from companies looking to sell.

The DEA came away with an ATR 500 that cost nearly $3 million more than it expected, despite the plane not meeting its technical and performance needs, and the agency not having the infrastructure in place to operate that model aircraft, the report says.

In reaching the decision to buy the plane, the agency only used only half of its technical evaluation process, leaving it unable to prove the plane was the one that best met its needs, auditors found.

Then began the process of fitting the new plane with surveillance equipment. The DEA handed the plane over to a DOD subcontractor in March 2012, but didn't record the transfer or enter into a memorandum of understanding with the subcontractor, meaning the agency couldn't ensure the proper modifications were made, according to the report.

Ten months later, the Global Discovery Program missed its delivery deadline for the first time. Nevertheless, the DOD shelled out $1.9 million on a contract to build a larger replacement hanger meant specifically to store the plane at the Kabul International Airport in Afghanistan, the report says.

Less than three years later, the DEA was out of the country.

By October 2014, the program had missed four more delivery dates and was out of money. The DOD considered scrapping the plane after sinking nearly $66 million into it, but ultimately decided not to because the cost of the remaining repairs was roughly equal to the market value of the plane, according to the report.

"More than 7 years after the DEA's major purchase of an aircraft to conduct surveillance and counternarcotics missions in Afghanistan, the ATR 500 modifications remain ongoing, and the aircraft has never flown in Afghanistan where a hangar, specifically built to house the aircraft, has stood since 2013," the report states. "In the meantime, the DEA has removed all aviation assets and ceased operations in Afghanistan, so it is unlikely the plane will ever fly there."

In addition to the slow repairs, auditors found that more than $2.3 million from the Global Discovery program account was improperly spent on maintenance on other airplanes, as well as for travel and training for people unrelated to the mission.

While the plane was being spruced up stateside, DEA planes in Afghanistan were overworked, the report found.

Between February 2012 and January 2015, the DEA had to turn down 1,000 mission requests, three-quarters of which it declined because it either did not have an aircraft to fulfill them or because the aircraft it did have was undergoing maintenance, according to the report.

When the DEA did fly, 79 percent of the time it was transporting people and equipment, rather than performing surveillance, the report found.

The ATR 500 did fly for the DEA, though not in Afghanistan, performing 227 "transport and extradition" missions in Colombia, Guatemala, Grand Cayman, Panama, Ecuador and Mexico between October 2008 and March 2012, the report found.

But for now, the plane remains in Delaware, having failed an April 2014 inspection by the Federal Aviation Administration over a number of "oblong holes" in its body. DEA and DOD officials believe the plane will never have all of the originally planned modifications, such as the fix-mounted cameras and radar system, which the DEA will have to add on later for about $3 million more, according to the report.

The next target date for delivery of the aircraft is in June, nearly eight years after the DEA first decided it needed to buy a plane.

In addition to the findings, the inspector general's report laid out 13 recommendations that the agency can adopt to ensure this kind of spending doesn't happen again. In a statement the DEA said it welcomed opportunities for improvement.

"Reviews by the Office of the Inspector General (OIG) are necessary and important, and DEA welcomes recommendations that make us better," a DEA spokesman said in a prepared statement. "DEA agrees that it can and should provide better oversight of its operational funding.

We are reviewing policies and procedures to ensure the limited resources allocated to DEA are utilized in the most responsible and effective way possible."